Energy Resources and Work& Power
Sources of Energy
Gravitation Potential Energy
Elastic Potential Energy
Heat transfers
Conduction
Is the transfer of heat energy through a substance by the vibration of atoms
Radiation
Is the transfer of energy by infrared waves it happens through space or through a material medium
Is an object that has been raised above the ground level
GPE (joules) = m (kg) x g (newtons) x h (meters)
Is the energy stored as a result of deformation of an elastic object
EPE (joules) = I/2 x k (spring constant) x X^2 (extension)
Kinetic Energy
KE (joules) = 1/2 x m (kg) x v^2 (m/s^2)
Is the energy of a moving object
Convection
Is the transfer of heat energy through fluids (liquid and gas) by the upward movement of warm or less dense region of fluid rising up and cold or less dense material sinking to the bottom
law of energy : energy can neither be lost nor created it can only be transferred from one store to another
Energy stores
Thermal
Eg: human bodies
Kinetic energy of particles in hotter objects articles have more thermal energy and vibrate faster
Magnetic
Eg: compasses
Energy stored when repelling poles have been pushed closer together or when attracting poles have been pulled farther apart
Chemical
Eg: food, muscles
The energy stored in chemical bonds
Kinetic
The energy of a moving object
Eg: bus
Electro static
Energy stored when repelling charges have been moved closer together or when attracting charges have been pulled further apart
Eg: thunderstorms
Elastic potential
Energy stored in an object is stretched or squashed
Eg: inflated balloons
Nuclear energy
Energy stored in the nucleus of an atom
Eg: uranium nuclear power
Gravitational potential
Energy of an object at height
Eg: airplanes
Energy transfers
Mechanical work
A force moving an object through a distance
Electrical work
Charge is moving due to a potential difference
Heating
Due to temperature difference caused electrically or by chemical reaction
There are transfer diagrams knows an Sankey diagrams
Energy resources
Renewable
Bio fuel
Energy store chemical
Uses transport
Power output medium
Wind
Energy stored kinetic
Power output low
Uses electricity generation
Hydroelectricity
Energy store gravitational potential
Uses electricity generation
Power output medium
Geothermal
Energy store thermal
Uses electricity generation
Power output medium
tides
Energy stores kinetic
Power output high
Uses electricity generation
Sun
Energy stored nuclear
Power output high
Uses electricity generation
Water waves
Energy stored kinetic
Uses electricity generation
Power output low
Non renewable
Fossil fuels
Energy stored chemical
Uses transport, heating, electricity generation.
Power output high
Nuclear fuels
Energy store nuclear
Uses electricity generation
Power output very high